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Hypoxia. The Department of Pathophysiology Guo lirong. Hypoxia. Main points to study. Definition of hypoxia (What is hypoxia?) Parameters of Blood Oxygen. Hypoxia. External respiration. Tissue cells. Blood. Circulation. Oxygen Supply. Oxygen Utilization. Hypoxia. Definition.
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Hypoxia The Department of Pathophysiology Guo lirong
Hypoxia Main points to study Definition of hypoxia (What is hypoxia?) Parameters of Blood Oxygen
Hypoxia External respiration Tissue cells Blood Circulation Oxygen Supply Oxygen Utilization
Hypoxia Definition Hypoxia is the commonest pathological process,which is defined as that cells can not obtain enough oxygen or can not fully utilize oxygen,thus leading to changes in their metabolism,function,or structure.
Hypoxia Parameters of Blood Oxygen 1.Partial pressure of oxygen(PO2) 2.Oxygen binding capacity(CO2 max) 3.Oxygen content(CO2) 4.Oxygen saturation( SO2)
Hypoxia Partial pressure of oxygen(PO2) 1.Definition:the tension produced by oxygen molecules physically dissolved in plasma. 2.Normal value:PaO2=13.3kPa(100mmHg) PvO2=5.33kPa(40mmHg)
Hypoxia Oxygen binding capacity (CO2max) 1. Definition:It is the maximum amount of oxygen that can be combined to hemoglobin in 100 ml of blood. 2.Normal value:20ml/dl
Hypoxia Oxygen content(CO2) 1.Definition:It is the actualcontent of oxygen in 100ml blood. 2.Normal value:CaO2=19ml/dl CvO2=14ml/dl
19ml/dl 14ml/dl A V O2 O2 O2 O2 O2 5ml/dl Arteriovenous oxygen content (Ca-vO2) Definition:It is the difference of oxygen content between arterial blood and mixed venous blood. Normal value: 5ml/dl
CO2-dissolved O2 • CO2max SO2 = 100% Hypoxia Oxygen saturation (SO2) Definition:It is the percentage of hemoglobin present as oxyhemoglobin. Normal value:SaO2=95%; SvO2=70%
P50 Definition:P50 is a parameter reflecting the affinity of Hb to oxygen; it is the O2 pressure required to sturate 50% of Hb. Normal value:26~28 mmHg
100 80 60 40 20 20 40 60 80 100 Dissociation curve of oxyhemoglobin Hypoxia Leftward-shifted curve: Hb Saturation (%) Rightward-shifted curve pH↓ 2,3-DPG↑ CO2↑ Temperature↑ PaO2 (mmHg)